The present invention relates to mounting straps for electrical switches, receptacles, and the like, and more particularly to novel and improved mounting straps which permit safer and more secure mounting of a wiring device in a "trade" or utility box.
Wiring devices such as light switches and receptacles are commonly mounted within the walls of domestic and commercial structures in open-front boxes attached to the studs or other supporting structure behind an opening in the wall surface. The boxes are of generally standard design and include threaded openings at the top and bottom to receive screws which pass through openings in ears or other such portions of the mounting strap, sometimes referred to as a yoke. The ears extend outwardly above and below the wiring device to which the mounting strap is securely attached.
The National Electric Code specifies that the surface of the box to which the mounting strap is secured shall be mounted not more than 1/8 inch behind the surrounding, outer wall surface. However, this rule is not always followed, and boxes are often mounted more than the allowed distance behind the wall surface. Also, the wall openings may be cut too large for the ends of the mounting strap to bridge the opening and rest against the wall surface. In such cases, if the screws passing through the mounting strap are tightened in the threaded openings of the box, the wiring device will be set too deeply in the wall. When inward pressure is exerted on the wiring device, it can move farther into the box. This results in cracking of the wall plate which is secured to the device in covering relation to the face thereof and which rests against the wall surface about the periphery of the opening. A cracked wall plate, in addition to the obviously objectionable appearance, creates potential safety problems.
It is a principal object of the present invention to provide a mounting strap which may be securely fastened to a box behind a wall opening while ensuring that the face of the wiring device is flush with the surrounding wall surface.
A further object is to provide a wiring device mounting strap having a deformable area around the mounting screw openings that allows the device to be always mounted flush with the wall surface with the screws securely fastened to draw the mount strap tightly against the mounting surface of the box.
In a more general sense, the object of the invention is to provide a wiring device mounting strap which permits a safer and more secure mounting of the wiring device and its associated wall plate.
Other objects will in part be obvious and will in part appear hereinafter.